   #?(:cljs (:require [test-utils.core :as tuc])
      :clj (:require (test-utils [core :as tuc]))))
 
-(def physical-quantities [:densty
+(def physical-quantities [:density
                           :energy
                           :force
                           :length

   (cond (= units :psi)
         (value-from-typical-range 5000 9000)
         (= units :kPa)
         ((convert-units-f :psi :kPa) (typical-monitor-pressure :psi))
         (= units :MPa)
         ((convert-units-f :kPa :MPa) (/ (typical-monitor-pressure :kPa) 1000)))))

(defn surface-treating-pressure-seq [arg]
  (cond (int? arg)

    (tuc/draw-normal mean sigma)))

(defn typical-monitor-pressure
  ([] (typical-monitor-pressure (rand-pressure-unit)))
  ([pressure-unit]
   (let [pressure-magnitude (cond (= pressure-unit :psi) (first (p-mon-seq))
                                  (= pressure-unit :kPa)
                                  (magnitude (pressure-as (typical-monitor-pressure :psi) :kPa)))]
     [pressure-magnitude pressure-unit])))

(defn typical-monitor-temperature
  ([] (let [units (rand-nth [:C :F])]
